Carl lewis set a world record for the 100.0-m run with a time of 9.86 s. if, after reaching the finish line, mr. lewis walked directly back to his starting point in 90.9 s, what is the magnitude of his average velocity for the 200.0 m?

The magnitude of his average velocity for the 200.0 m is zero.

Explanation:

Given that,

Distance = 100.0 m

Time = 9.86 s

Now, back to his starting point

Time = 90.9 s

Average velocity :

Average velocity is equal to the total displacement divided by the total time.

In mathematical form,

Where, D = Displacement

t = time

He started at the Start line, and ended at the Start Line.. his Net displacement will be Zero so the average velocity will be

Using formula of average velocity,

Hence, The magnitude of his average velocity for the 200.0 m is zero.

russian is not my first language, so i'm afraid i can't write out an answer in russian, but hopefully you can find a way to do so. here's my best translation of the problem: you're given a plot of a particle's position in one-dimensional space over time, and you're asked to find either the total distance traveled by the particle after 6 seconds had elapsed, or the total displacement of the particle after 6 seconds.

if you want the total distance traveled, you would first need to determine the particle's velocity as a function of time, then integrate that over the 6-second interval. we know the position function is quadratic with roots at 0 and 6, so we have

where is unknown. because the position is parabolic, there is symmetry about the midpoint at , and we know that

so that the position function is

which means the velocity is

then the total distance traveled is

so the total distance traveled is 20 m.

on the other hand, if you want to find displacement: the particle starts at and ends at , so its displacement is 0.